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        function a(str, s) {
            let count = 0;
            // console.log(s,"---");
            for (let i = 0; i < str.length; i++) {
                // console.log(str[i],str[i]===s,str[i].toUpperCase()===s.toUpperCase(),);
                if (str[i].toUpperCase()===s.toUpperCase()) {
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       console.log(a("ABCaD",
"a"));
console.log(a("c",
"j"));
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